Bearing main shaft structure and grinding machine

Abstract

The invention discloses a bearing spindle structure and a grinding machine. The bearing spindle structure comprises a shell; the shaft body is rotationally arranged in the shell in a penetrating mode, the shaft body comprises a first shaft part and a second shaft part, and the first shaft part is close to the end of the shaft body relative to the second shaft part; the first bearing structure comprises a first inner ferrule, a first outer ferrule and a first rolling assembly arranged between the first inner ferrule and the first outer ferrule, the first inner ferrule is sleeved with a first through hole extending in the axial direction of the shaft body, and the first bearing structure is provided with an axial adjustable clearance and a radial adjustable clearance; the first inner ferrule is connected with the first shaft part in an interference fit mode, and the outer diameter of the first shaft part is gradually increased in the direction close to the second shaft part. And the end cover is used for fixing the first outer ferrule. The main shaft has the beneficial effects that the rotation precision of the first bearing structure can be improved when the rotating speed of the main shaft is relatively high, so that the machining quality is ensured.

Description

Technical Field

[0001] The invention is used in the field of grinding machines and relates to an accessory of a grinding machine, in particular to a bearing spindle structure and a grinding machine. Background Art

[0002] As the level of industrialization gradually improves, the manufacturing level of the manufacturing industry is also improving accordingly, which puts high demands on the processing performance of the grinder. The performance of the spindle, as the core functional component of the grinder, is directly related to the processing level of the grinder. The performance of the spindle is often affected by many factors such as the dimensional tolerance of its components, matching accuracy, bearing preload, and motor, among which the matching between the bearing and the shaft is particularly important.

[0003] When performing grinding, for parts made of different materials, it is necessary to select the appropriate spindle speed based on the characteristics of the workpiece material. When the spindle speed increases, the vibration of the bearing structure increases, which can easily affect the rotation accuracy of the bearing and thus affect the processing quality. Summary of the invention

[0004] The object of the present invention is to provide a bearing spindle structure to solve the problem of reduced rotation accuracy caused by bearing vibration when the spindle speed increases.

[0005] The present invention is achieved through the following technical solutions.

[0006] A bearing spindle structure, comprising: case; A shaft body is rotatably disposed in the housing, the shaft body comprising a first shaft portion and a second shaft portion, the first shaft portion being closer to an end of the shaft body relative to the second shaft portion; A first bearing structure, comprising a first inner ring, a first outer ring and a first rolling assembly arranged therebetween, wherein the first inner ring is provided with a first through hole extending axially along the shaft body, the first bearing structure has an axially adjustable clearance and a radially adjustable clearance, the first inner ring is connected to the first shaft portion by interference fit, and the outer radial direction of the first shaft portion gradually increases in a direction approaching the second shaft portion; The end cover is used to fix the first outer ring.

[0007] As a further improvement of the present invention, a locking component is provided on the shaft body, and the locking component is used to apply an axial locking force to the first inner ring. The locking component is provided with a second through hole along the axial direction, and the locking component is movably sleeved on the shaft body so that it can move axially along the shaft body to match the position of the first inner ring on the first shaft portion.

[0008] As a further improvement of the present invention, the locking component is threadedly matched with the shaft body, the shaft body is provided with an external thread, and the second through hole is provided with an internal thread that matches with the external thread.

[0009] As a further improvement of the present invention, the first rolling assembly includes a plurality of first rolling bodies, the first rolling bodies are cylindrical, and an inwardly recessed annular rolling groove is provided on the side of the first inner ring close to the first outer ring. The first rolling body is arranged in the annular rolling groove and rollingly cooperates with the annular rolling groove and the first outer ring.

[0010] As a further improvement of the present invention, the shell is recessed inwardly at a position corresponding to the first shaft portion to form an annular limiting portion, the first outer ring is arranged in the shell and one end abuts against the annular limiting portion, and the end cover is arranged at the end of the shell and applies an axial clamping force to the first outer ring to press the first outer ring onto the annular limiting portion.

[0011] As a further improvement of the present invention, the end cover is provided with a third through hole allowing the shaft body to pass through, the end cover is sleeved outside the shaft body, a fastener is provided between the end cover and the shell, a first connecting hole is provided on the shell, a second connecting hole is provided on the end cover, and the fastener passes through the first connecting hole and the second connecting hole to fix the end cover and the shell.

[0012] As a further improvement of the present invention, it further includes a second bearing structure, wherein the first bearing structure is arranged at the first end of the shaft body, and the second bearing structure is arranged at the second end of the shaft body.

[0013] As a further improvement of the present invention, the second bearing structure includes a second inner ring, a second outer ring and a second rolling assembly arranged therebetween, the second rolling assembly includes a plurality of second rolling bodies, the second rolling bodies are spherical, and the plurality of second rolling bodies are in rolling cooperation with the second inner ring and the second outer ring.

[0014] A grinding machine comprises a bearing spindle structure in the above technical solution.

[0015] Beneficial effects of the present invention: According to the different rotation speeds of the main shaft structure during operation, the installation position of the first inner ring on the first shaft portion is adjusted, that is, the stress of the first shaft portion on the first inner ring is changed, thereby changing the radial clearance of the first bearing structure, and then adjusting the stiffness of the first bearing structure. On the one hand, when the shaft body rotates at a high speed, the first bearing structure has a higher stiffness, ensuring the rotational accuracy and stability of the first bearing structure during rotation, thereby ensuring the processing quality. On the other hand, when the shaft body rotates at a low speed, the wear of the first rolling component can be reduced, thereby increasing the service life of the main shaft structure and reducing production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings to help understand the purpose and advantages of the present invention, wherein: Figure 1 It is a structural schematic diagram of a bearing spindle structure of the present invention; Figure 2 This is an internal structure diagram of a bearing spindle structure of the present invention; Figure 3 for Figure 2 Schematic diagram of the structure of part A; Figure 4 is a schematic diagram of the structure of the shell; Figure 5 It is a schematic diagram of the structure of the end cover. DETAILED DESCRIPTION

[0017] The present invention is further described in detail below based on the accompanying drawings and implementation examples.

[0018] The directional terms such as up, down, left, right, front, back, front, back, top, bottom, etc. mentioned or may be mentioned in this specification are defined relative to the structures shown in the drawings. The words "inside" and "outside" refer to the direction toward or away from the geometric center of a specific component, respectively. They are relative concepts, and therefore may change accordingly according to different locations and different usage conditions. Therefore, these or other directional terms should not be interpreted as restrictive terms.

[0019] Embodiment 1: A bearing spindle structure, used in a grinding machine, referring to Figures 1 to 5 , including a shell 1, a shaft body 2, a first bearing structure 3 and an end cover 4, wherein the shaft body 2 is rotatably arranged in the shell 1, and includes a first shaft portion 21 and a second shaft portion 22, the first shaft portion 21 is closer to the end of the shaft body 2 than the second shaft portion 22, the first bearing structure 3 includes a first inner ring 31, a first outer ring 32 and a first rolling assembly rollingly connected therebetween, the first inner ring 31 is sleeved with a first through hole 311 extending axially along the shaft body 2, the end cover 4 presses and fixes the first outer ring 32 in the shell 1, the first bearing structure 3 is provided with an axially adjustable clearance and a radially adjustable clearance, the first inner ring 31 is connected to the first shaft portion 21 by interference fit, the first shaft portion 21 is conical, that is, the first through hole 311 is a tapered hole corresponding to the first shaft portion 21, and the outer radial direction of the first shaft portion 21 gradually increases in the direction approaching the second shaft portion 22.

[0020] In this embodiment, when installing the first inner ring 31, the first inner ring 31 is heated. Due to thermal expansion and contraction, the first through hole 311 will become larger accordingly. Then, the first through hole 311 is inserted into the shaft body 2 and a certain pressure is applied. After cooling, the first through hole 311 returns to its original shape so that the first inner ring 31 is tightly connected to the shaft body 2. At the same time, since the first shaft body 2 is tapered, the first inner ring 31 is subjected to axial and radial pressure from the shaft body 2. Moreover, the closer the installation position of the first inner ring 31 is to the second shaft portion 22, the larger the first inner ring 31 is. The greater the axial and radial pressure exerted on 31 by the shaft body 2, the more the first inner ring 31 will be deformed under the force, so that the radial clearance of the first bearing structure 3 is reduced and the rigidity of the first bearing structure 3 is increased. Therefore, when the rotation speed of the shaft body 2 increases, the position of the first inner ring 31 on the first shaft body 2 is changed, and it is installed at a position closer to the second shaft portion 22, that is, the rigidity of the first bearing structure 3 is improved, so that the first bearing structure 3 can maintain sufficient rotational accuracy when the rotation speed of the shaft body 2 is relatively high, thereby improving the applicability of the spindle structure.

[0021] Generally speaking, when the bearing is in use, the rolling element is prone to wear, and the greater the rotation speed of the shaft body 2, the faster the rolling element wears, the smaller the radial clearance of the bearing, the faster the rolling element wears, and when the rolling element wears to a certain extent, the rotation accuracy of the bearing cannot be guaranteed, resulting in a short service life of the bearing. At this time, the bearing needs to be replaced to ensure the rotation accuracy of the shaft, which is not only time-consuming and labor-intensive, but also costly. In this embodiment, in order to increase the service life of the first bearing structure 3 and reduce production costs, when the rotation speed of the main shaft is reduced, the position of the first inner ring 31 on the first shaft body 2 can be changed, and it can be installed at a position relatively far away from the second shaft portion 22, thereby reducing the wear speed of the first rolling assembly and increasing its service life.

[0022] In this embodiment, in response to the different speeds of the main shaft structure during operation, the installation position of the first inner ring 31 on the first shaft portion 21 is adjusted, the stress of the first shaft portion 21 on the first inner ring 31 is changed, thereby changing the radial clearance of the first bearing structure 3 and adjusting the stiffness of the first bearing structure 3. On the one hand, when the rotation speed of the shaft body 2 is high, the first bearing structure 3 has a higher stiffness, ensuring the rotational accuracy and stability of the first bearing structure 3 during rotation, and ensuring the processing accuracy of the workpiece. On the other hand, when the rotation speed of the shaft body 2 is low, the wear of the first rolling assembly can be reduced, thereby increasing the service life of the main shaft structure and reducing production costs.

[0023] In this embodiment, a locking component 5 is provided on the shaft body 2, and one end of the locking component 5 close to the first inner ring 31 directly or indirectly abuts against the first inner sleeve. The locking component 5 is used to apply an axial locking force to the first inner ring 31 to fix the first inner ring 31. The locking component 5 is provided with a second through hole 51 along the axial direction, and the locking component 5 is movably sleeved on the shaft body 2 so that it can move axially along the shaft body 2. When the first inner ring 31 changes, the position of the locking component 5 can be adjusted so that the locking component 5 can always provide sufficient axial locking force to the first inner ring 31, that is, match the position of the first inner ring 31 on the first shaft portion 21 to ensure the connection stability between the first inner ring 31 and the shaft body 2.

[0024] In this embodiment, the locking component 5 and the shaft body 2 are threadedly matched. Specifically, the shaft body 2 is provided with an external thread, and the second through hole 51 is provided with an internal thread that matches the external thread. On the one hand, the threaded matching method makes the connection between the locking component 5 and the shaft body 2 relatively stable, that is, the locking component 5 can apply a relatively stable locking force to the first inner ring 31. On the other hand, when the position of the locking component 5 needs to be adjusted, the locking component 5 needs to be rotated to drive the locking component 5 to move axially along the shaft body 2, which is easy to operate.

[0025] In this embodiment, the shell 1 is recessed inward to form an annular limiting portion 11 at a position corresponding to the first shaft portion 21, the first outer ring 32 is arranged in the shell 1 and one end abuts against the annular limiting portion 11, the end cover 4 is arranged on the end of the shell 1 and applies an axial clamping force to the first outer ring 32 to press the first outer ring 32 against the annular limiting portion 11, thereby fixing the first outer ring 32 in the shell 1.

[0026] In this embodiment, the end cover 4 is provided with a third through hole 41 allowing the shaft body 2 to pass through, the end cover 4 is sleeved on the outside of the shaft body 2, and a fastener (not shown in the figure) is provided between the end cover 4 and the shell 1, the shell 1 is provided with a first connecting hole 12, and the end cover 4 is provided with a second connecting hole 42. The fastener passes through the first connecting hole 12 and the second connecting hole 42 to fix the end cover 4 and the shell 1. The fastener here can be set as a screw, and the first connecting hole 12 can be set as a screw hole, which is convenient for removing the end cover 4 from the shell 1. When the first outer ring 32 is damaged, it is convenient to replace and maintain the first outer ring 32.

[0027] In this embodiment, the first rolling assembly includes a plurality of first rolling bodies 33, the first rolling bodies 33 are cylindrical, and an inwardly recessed annular rolling groove is provided on the side of the first inner ring 31 close to the first outer ring 32. The first rolling body 33 is provided in the annular rolling groove and rollingly cooperates with the annular rolling groove and the first outer ring 32. The cylindrical rolling body can withstand a large load and is suitable for high-speed rotation scenarios.

[0028] At the same time, in order to ensure the stability of the shaft body 2 during rotation, the spindle structure also includes a second bearing connection structure. The first bearing structure 3 is arranged at the first end of the shaft body 2, and the second bearing structure 7 is arranged at the second end of the shaft body 2. The first end here refers to the end of the shaft body 2 close to the workpiece to be ground, and the second end refers to the end of the shaft body 2 close to the motor. The first bearing structure 3 and the second bearing structure 7 help to reduce the vibration and deformation of the shaft body 2 during high-speed operation, which helps to improve the processing accuracy.

[0029] In this embodiment, the second bearing structure 7 includes a second inner ring 71, a second outer ring 72 and a second rolling assembly arranged therebetween. The second rolling assembly includes a plurality of second rolling bodies 73. The second rolling bodies 73 are spherical. The plurality of second rolling bodies 73 roll with the second inner ring 71 and the second outer ring 72. The second bearing structure 7 here is an angular contact ball bearing, which has a high rigidity and helps to maintain the stability of the shaft 2 during rotation.

[0030] Embodiment 2: A grinding machine comprises a bearing spindle structure in the above embodiment.

[0031] Finally, it should be noted that the above implementation cases are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned implementation cases, those skilled in the art should understand that they can still modify the technical solutions recorded in the aforementioned implementation cases, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the implementation cases of the present invention.

Claims

1. A bearing spindle structure, characterized in that: include: Housing (1); A shaft body (2) is rotatably disposed in the housing (1), the shaft body (2) comprising a first shaft portion (21) and a second shaft portion (22), the first shaft portion (21) being closer to an end of the shaft body (2) relative to the second shaft portion (22); A first bearing structure (3) comprises a first inner ring (31), a first outer ring (32) and a first rolling assembly arranged therebetween, the first inner ring (31) being provided with a first through hole (311) extending axially along the shaft body (2), the first bearing structure (3) having an axially adjustable clearance and a radially adjustable clearance, the first inner ring (31) being connected to the first shaft portion (21) by interference fit, and the outer radial direction of the first shaft portion (21) gradually increasing in a direction approaching the second shaft portion (22); An end cover (4) is used to fix the first outer ring (32).

2. A bearing spindle structure according to claim 1, characterized in that: The shaft body (2) is provided with a locking component (5), the locking component (5) being used to apply an axial locking force to the first inner ring (31), the locking component (5) being provided with a second through hole (51) along the axial direction, and the locking component (5) being movably sleeved on the shaft body (2) so as to be able to move axially along the shaft body (2) to match the position of the first inner ring (31) on the first shaft portion (21).

3. A bearing spindle structure according to claim 2, characterized in that: The locking component (5) is threadably matched with the shaft body (2); the shaft body (2) is provided with an external thread; and the second through hole (51) is provided with an internal thread that matches the external thread.

4. A bearing spindle structure according to claim 1, characterized in that: The housing (1) is recessed inwardly at a position corresponding to the first shaft portion (21) to form an annular limiting portion (11); the first outer ring (32) is arranged in the housing (1) and one end thereof abuts against the annular limiting portion (11); the end cover (4) is arranged at an end of the housing (1) and applies an axial pressing force to the first outer ring (32) so as to press the first outer ring (32) onto the annular limiting portion (11).

5. A bearing spindle structure according to claim 4, characterized in that: The end cover (4) is provided with a third through hole (41) for allowing the shaft body (2) to pass through, the end cover (4) is sleeved outside the shaft body (2), a fastener is provided between the end cover (4) and the housing (1), the housing (1) is provided with a first connecting hole (12), the end cover (4) is provided with a second connecting hole (42), and the fastener passes through the first connecting hole (12) and the second connecting hole (42) to fix the end cover (4) and the housing (1).

6. A bearing spindle structure according to claim 1, characterized in that: The first rolling assembly comprises a plurality of first rolling bodies (33), the first rolling bodies (33) being cylindrical, a side of the first inner ring (31) close to the first outer ring (32) being provided with an inwardly recessed annular rolling groove, the first rolling bodies (33) being arranged in the annular rolling groove and rollingly engaging with the annular rolling groove and the first outer ring (32).

7. A bearing spindle structure according to claim 6, characterized in that: It also comprises a second bearing structure (7), wherein the first bearing structure (3) is arranged at the first end of the shaft body (2), and the second bearing structure (7) is arranged at the second end of the shaft body (2).

8. A bearing spindle structure according to claim 7, characterized in that: The second bearing structure (7) comprises a second inner ring (71), a second outer ring (72) and a second rolling assembly arranged therebetween, the second rolling assembly comprising a plurality of second rolling bodies (73), the second rolling bodies (73) being spherical, and the plurality of second rolling bodies (73) rollingly engaging with the second inner ring (71) and the second outer ring (72).

9. A grinding machine, characterized in that: A bearing spindle structure comprising any one of claims 1 to 8.

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